Export to PDF Image Corruption on MM v9 on Windows 8

I have MM 9 running on Windows 8. Everything seems to be working OK apart from the export to PDF where the graphics are corrupted. I have reinstalled the PDX XChange program as has been suggested for other PDF issues and rebooted but no joy.

This might me resolved by selecting a higher PDF specification version in the PDF Export Setting screen when exporting the map to PDF. If that doesn't help, you can try to turn off the gradients inside the topics by going to 'File' > 'Options' > 'Visual Effects' > 'Show fill color gradients'